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1.
Genes Dev ; 31(9): 927-938, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28536146

RESUMO

Stomata are microscopic openings that allow for the exchange of gases between plants and the environment. In Arabidopsis, stomatal patterning is specified by the ERECTA family (ERf) receptor kinases (RKs), the receptor-like protein (RLP) TOO MANY MOUTHS (TMM), and EPIDERMAL PATTERNING FACTOR (EPF) peptides. Here we show that TMM and ER or ER-LIKE1 (ERL1) form constitutive complexes, which recognize EPF1 and EPF2, but the single ERfs do not. TMM interaction with ERL1 creates a binding pocket for recognition of EPF1 and EPF2, indicating that the constitutive TMM-ERf complexes function as the receptors of EPF1 and EPF2. EPFL9 competes with EPF1 and EPF2 for binding to the ERf-TMM complex. EPFL4 and EPFL6, however, are recognized by the single ERfs without the requirement of TMM. In contrast to EPF1,2, the interaction of EPFL4,6 with an ERf is greatly reduced in the presence of TMM. Taken together, our data demonstrate that TMM dictates the specificity of ERfs for the perception of different EPFs, thus functioning as a specificity switch for the regulation of the activities of ERfs.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica de Plantas , Estômatos de Plantas/crescimento & desenvolvimento , Arabidopsis/metabolismo , Estômatos de Plantas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Especificidade por Substrato
2.
J Cell Biochem ; 125(1): 115-126, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38079224

RESUMO

Asperosaponin VI (ASA VI) is a bioactive triterpenoid saponin extracted from Diptychus roots, of Diptyl, and has previously shown protective functions in rheumatoid arthritis and sepsis. This study investigates the effects and molecular mechanisms of ASA VI on skeletal muscle regeneration in a cardiotoxin (CTX)-induced skeletal muscle injury mouse model. Mice were subjected to CTX-induced injury in the tibialis anterior and C2C12 myotubes were treated with CTX. Muscle fiber histology was analyzed at 7 and 14 days postinjury. Apoptosis and autophagy-related protein expression were evaluated t s by Western blot, and muscle regeneration markers were quantified by quantitative polymerase chain reaction. Docking studies, cell viability assessments, and glycogen synthase kinase-3ß (GSK-3ß) activation analyses were performed to elucidate the mechanism. ASA VI was observed to improve muscle interstitial fibrosis, remodeling, and performance in CTX-treated mice, thereby increased skeletal muscle size, weight, and locomotion. Furthermore, ASA VI modulated the expression of apoptosis and autophagy-related proteins through GSK-3ß inhibition and activated the transcription of regeneration genes. Our results suggest that ASA VI mitigates skeletal muscle injury by modulating apoptosis and autophagy via GSK-3ß signaling and promotes regeneration, thus presenting a probable therapeutic agent for skeletal muscle injury.


Assuntos
Músculo Esquelético , Saponinas , Camundongos , Animais , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Músculo Esquelético/metabolismo , Apoptose , Saponinas/farmacologia
3.
J Med Internet Res ; 26: e55121, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820583

RESUMO

BACKGROUND: As an important platform for researchers to present their academic findings, medical journals have a close relationship between their evaluation orientation and the value orientation of their published research results. However, the differences between the academic impact and level of disruptive innovation of medical journals have not been examined by any study yet. OBJECTIVE: This study aims to compare the relationships and differences between the academic impact, disruptive innovation levels, and peer review results of medical journals and published research papers. We also analyzed the similarities and differences in the impact evaluations, disruptive innovations, and peer reviews for different types of medical research papers and the underlying reasons. METHODS: The general and internal medicine Science Citation Index Expanded (SCIE) journals in 2018 were chosen as the study object to explore the differences in the academic impact and level of disruptive innovation of medical journals based on the OpenCitations Index of PubMed open PMID-to-PMID citations (POCI) and H1Connect databases, respectively, and we compared them with the results of peer review. RESULTS: First, the correlation coefficients of the Journal Disruption Index (JDI) with the Journal Cumulative Citation for 5 years (JCC5), Journal Impact Factor (JIF), and Journal Citation Indicator (JCI) were 0.677, 0.585, and 0.621, respectively. The correlation coefficient of the absolute disruption index (Dz) with the Cumulative Citation for 5 years (CC5) was 0.635. However, the average difference in the disruptive innovation and academic influence rankings of journals reached 20 places (about 17.5%). The average difference in the disruptive innovation and influence rankings of research papers reached about 2700 places (about 17.7%). The differences reflect the essential difference between the two evaluation systems. Second, the top 7 journals selected based on JDI, JCC5, JIF, and JCI were the same, and all of them were H-journals. Although 8 (8/15, 53%), 96 (96/150, 64%), and 880 (880/1500, 58.67%) of the top 0.1%, top 1%, and top 10% papers selected based on Dz and CC5, respectively, were the same. Third, research papers with the "changes clinical practice" tag showed only moderate innovation (4.96) and impact (241.67) levels but had high levels of peer-reviewed recognition (6.00) and attention (2.83). CONCLUSIONS: The results of the study show that research evaluation based on innovative indicators is detached from the traditional impact evaluation system. The 3 evaluation systems (impact evaluation, disruptive innovation evaluation, and peer review) only have high consistency for authoritative journals and top papers. Neither a single impact indicator nor an innovative indicator can directly reflect the impact of medical research for clinical practice. How to establish an integrated, comprehensive, scientific, and reasonable journal evaluation system to improve the existing evaluation system of medical journals still needs further research.


Assuntos
Bibliometria , Fator de Impacto de Revistas , Publicações Periódicas como Assunto , Publicações Periódicas como Assunto/estatística & dados numéricos , Humanos , Pesquisa Biomédica/estatística & dados numéricos
4.
J Psycholinguist Res ; 53(3): 33, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38526606

RESUMO

This study uses a data-driven approach to mine the distribution of personality traits among Chinese people in the Chinese social context. Based on the hypothesis of personality lexicology, word embedding technology was employed in machine learning to mine personality vocabulary from Tencent's word embedding database. More than 10,000 Chinese personality descriptors were extracted and analyzed using Gaussian Mixture Model Cluster and Hierarchical clustering analysis. The data was collected from 658 Chinese people randomly from all parts of China through an online questionnaire method. The results reveal six personality traits in the Chinese context, expanding the personality thesaurus and providing examples to illustrate each trait. The findings coincide with previous research on the five-factor model, which partially describes the personality traits of Chinese people, but does not offer a complete explanation of their typical social behavior patterns. Additionally, the study supports the notion of cultural particularity in personality traits. The approach used in this study offers a richer personality vocabulary than traditional personality mining methods, and word embedding technology captures richer semantic information in Chinese. The six Chinese personality traits identified in this study will also be used to explore how to quantify and evaluate personality traits based on word embedding and personality descriptors.


Assuntos
População do Leste Asiático , Personalidade , Vocabulário , Humanos , Semântica , Tecnologia
5.
Zhongguo Zhong Yao Za Zhi ; 47(20): 5550-5555, 2022 Oct.
Artigo em Zh | MEDLINE | ID: mdl-36471972

RESUMO

Chemical constituents of ethanol extract of Pulsatillae Radix were investigated. The n-butanol fraction of ethanol extract of Pulsatillae Radix was isolated and purified by macroporous resin and silica gel column chromatography and semi-preparative high performance liquid chromatography. The triterpenoid glycosides were identified by multiple spectral methods. Six compounds were obtained from the n-butanol fraction of ethanol extract of Pulsatillae Radix and identified as 23-aldehyde-cussosaponin C(1), cussosaponin C(2), anemoside B4(3), akebia saponin D(4), pulchinenoside E3(5), and hederacoside C(6). Among them, compound 1 was a new compound.


Assuntos
1-Butanol , Medicamentos de Ervas Chinesas , Glicosídeos/química , Etanol/química
6.
Angew Chem Int Ed Engl ; 61(39): e202209642, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-35909226

RESUMO

Quinone compounds, which are capable of accommodating proton (H+ ), are emerging electrodes in aqueous batteries. However, the storage mechanism of proton in quinone compounds is less known and the energy/power density of quinone-based proton battery is still limited. Here we design a series of quinone anodes and study their electrochemical properties in acidic electrolyte, in which tetramethylquinone (TMBQ) delivers a high capacity of 300 mAh g-1 with an extremely low polarization of 20 mV at 1 C, and maintains over 50 % theoretical capacity in less than 16 seconds. The fast kinetics of TMBQ is attributed to the continuous H+ migration channel, high H+ diffusion coefficient (10-6  cm2 s-1 ), and low H+ migration energy barrier (0.26 eV). When coupling with MnO2 cathode, the battery shows a long lifespan of 4000 cycles with a capacity retention of 77 % at 5 C. This study reveals the proton transport in quinone-electrodes and offers new insights to design advanced aqueous batteries.

7.
Theor Appl Genet ; 133(4): 1303-1312, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31996972

RESUMO

KEY MESSAGE: BoFL, a candidate gene conferring the feathered-leaved trait in ornamental kale, is located in a 374.532-kb region on chromosome C9. Leaf shape is an important economic trait in ornamental kale (Brassica oleracea var. acephala). Identifying the genes that influence leaf shape would provide insight into the mechanism underlying leaf development. In this study, we constructed F1, F2, BC1P1, BC1P2, and F2:3 populations from a cross between a feathered-leaved inbred line, F0819, and a smooth-leaved inbred line, S0835, of ornamental kale. Genetic analysis showed that the feathered-leaved trait was controlled by a semi-dominant gene, BoFL. Using bulked segregant analysis sequencing, we mapped the BoFL gene to a 4.17-Mb interval on chromosome C9. Next, we narrowed down the candidate region to 374.532-kb by fine-scale mapping between the two flanking markers INDEL940 and INDEL5443. We identified 38 genes in the candidate region, among which only Bo9g184610 showed significant variation in expression level between the two parental lines. Sequencing of the gene in the parental lines identified three single-nucleotide polymorphism (SNP) differences, containing two nonsynonymous and one synonymous SNPs, which resulted in coding variations of an aspartate and a phenylalanine residue in F0819, but an alanine and a leucine residue in S0835. A cleaved amplified polymorphic sequence (CAPS) marker, CAPS4610, corresponding to the first nonsynonymous SNP co-segregated with the leaf shape trait. We thus speculated that the gene conferring the feathered-leaved trait is BoALG10, a homolog of ALG10, which encodes an alpha-1,2-glucosyltransferase in Arabidopsis thaliana. This work will be useful for understanding the mechanism of leaf development and provides important information for the breeding of kale with novel leaf shapes.


Assuntos
Brassica/genética , Genes de Plantas , Mapeamento Físico do Cromossomo , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Sequência de Bases , Segregação de Cromossomos/genética , Cromossomos de Plantas/genética , Cruzamentos Genéticos , Regulação da Expressão Gênica de Plantas , Estudos de Associação Genética , Marcadores Genéticos , Fenótipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
8.
Adv Exp Med Biol ; 1172: 119-141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31628654

RESUMO

The nucleotide-binding domain (NBD) and leucine-rich repeat (LRR) containing (NLR) proteins are a large family of intracellular immune receptors conserved in both animals and plants. Mammalian NLRs function as pattern recognition receptors (PRRs) to sense pathogen-associated molecular patterns (PAMPs) or host-derived danger associated molecular patterns (DAMPs). PAMP or DAMP perception activates NLRs which consequently recruit pro-caspase-1 directly or indirectly. These sequential events result in formation of large multimeric protein complexes termed inflammasomes that mediate caspase-1 activation for pyroptosis and cytokine secretion. Recent structural and biochemical studies provide significant insights into the acting mechanisms of NLR proteins. In this chapter, we review and discuss these studies concerning autoinhibition, ligand recognition, activation of NLRs, and assembly of NLR inflammasomes.


Assuntos
Inflamassomos , Proteínas NLR , Animais , Inflamassomos/biossíntese , Inflamassomos/imunologia , Proteínas NLR/química , Proteínas NLR/imunologia , Plantas , Receptores de Reconhecimento de Padrão
9.
Int J Biol Macromol ; 278(Pt 3): 134853, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39163955

RESUMO

Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Sepsis causes a high mortality rate and current treatment focuses on supportive therapies but lacks specific therapeutic targets. Notably, sirtuins (SIRTs) shows potential clinical application in the treatment of sepsis. It has been demonstrated that SIRTs, the nicotinamide adenine dinucleotide+(NAD+)-dependent deacetylases that regulate key signaling pathways in eukaryotes and prokaryotes, are involved in a variety of biological processes. To date, seven mammalian yeast Sir2 homologs have been identified. SIRTs can regulate inflammation, oxidative stress, apoptosis, autophagy, and other pathways that play important roles in sepsis-induced organ dysfunction. However, the existing studies on SIRTs in sepsis are too scattered, and there is no relevant literature to integrate them. This review innovatively summarizes the different mechanisms of SIRTs in sepsis organ dysfunction according to the different systems, and focuses on SIRT agonists, inhibitors, and targeted drugs that have been proved to be effective in the treatment of sepsis, so as to integrate the clinical research and basic research closely. We searched PubMed for all literature related to SIRTs and sepsis since its inception using the following medical subject headings: sirtuins, SIRTs, and sepsis. Data on the mechanisms of SIRTs in sepsis-induced organ damage and their potential as targets for disease treatment were extracted.

10.
Microsyst Nanoeng ; 10: 55, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38680522

RESUMO

Sensing of both temperature and strain is crucial for various diagnostic and therapeutic purposes. Here, we present a novel hydrogel-based electronic skin (e-skin) capable of dual-mode sensing of temperature and strain. The thermocouple ion selected for this study is the iodine/triiodide (I-/I3-) redox couple, which is a common component in everyday disinfectants. By leveraging the thermoelectric conversion in conjunction with the inherent piezoresistive effect of a gel electrolyte, self-powered sensing is achieved by utilizing the temperature difference between the human body and the external environment. The composite hydrogels synthesized from polyvinyl alcohol (PVA) monomers using a simple freeze‒thaw method exhibit remarkable flexibility, extensibility, and adaptability to human tissue. The incorporation of zwitterions further augments the resistance of the hydrogel to dehydration and low temperatures, allowing maintenance of more than 90% of its weight after 48 h in the air. Given its robust thermal current response, the hydrogel was encapsulated and then integrated onto various areas of the human body, including the cheeks, fingers, and elbows. Furthermore, the detection of the head-down state and the monitoring of foot movements demonstrate the promising application of the hydrogel in supervising the neck posture of sedentary office workers and the activity status. The successful demonstration of self-powered on-body temperature and strain sensing opens up new possibilities for wearable intelligent electronics and robotics.

11.
Radiother Oncol ; 197: 110340, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38797492

RESUMO

PURPOSE: This study aimed to reveal the association of fatigue with weekly changes in the body composition in patients with nasopharyngeal carcinoma (NPC) and identified the independent strength. METHODS: Four body composition indexes and fatigue were assessed before treatment (T0, baseline) and once a week throughout radiotherapy (T1-T7). Generalized additive mixed models (GAMMs) were used to explore the trajectories and longitudinal relationships of fatigue and weekly changes in body composition. The marginal structural model (MSM) was used to control the effect of depression and anxiety. RESULTS: The trajectories of fatigue in 105 participants reached a peak in the fifth week, and changes in body composition started appearing from the second week. Four body composition indexes, weight, body mass index (BMI), body fat rate, and lean body weight loss weekly were positively associated with fatigue. High magnitude of effects was revealed when anxiety and depression were controlled as time-dependent confounders. The positive associations with fatigue were manifested in patients aged >53 years, those with senior high and above education, no drinking, >5000 Y/month of family inflow, ≥ stage III, or those receiving a dose of ≥70 Gy, ≥3 cycles of induced chemotherapy, and ≤1 cycle of concurrent chemotherapy. CONCLUSIONS: Loss of weight, BMI, body fat rate, and lean body weight could be used to independently evaluate the development of fatigue in patients with NPC during radiotherapy. Positive associations between fatigue and weekly body composition loss were found in patients with certain characteristics.


Assuntos
Composição Corporal , Fadiga , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Fadiga/etiologia , Estudos Longitudinais , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Adulto , Índice de Massa Corporal , Idoso , Redução de Peso
12.
Cancer Med ; 13(8): e7191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659395

RESUMO

BACKGROUND: Patients with nasopharyngeal carcinoma (NPC) undergoing radiotherapy experience significant fatigue, which is frequently underestimated due to the lack of objective indicators for its evaluation. This study aimed to explore the longitudinal association between fatigue and nutrition status 1 week in advance. METHODS: From January 2021 to June 2022, a total of 105 NPC patients who received intensity-modulated radiation therapy were enrolled in the observational longitudinal study. The significant outcomes, including the Piper Fatigue Scale-12 (PFS-12), the Scored Patient-Generated Subjective Global Assessment (PG-SGA), four body composition indices, and the Hospital Anxiety and Depression Scale (HADS), were assessed weekly from pre-treatment until the completion of radiotherapy (T0-T7) to explore their relationship. RESULTS: The trajectories of PFS-12 and all dimensions for 105 participants reached a peak during the fifth week. Sensory fatigue consistently received the highest scores (T0 = 1.60 ± 2.20, T5 = 6.15 ± 1.57), whereas behavior fatigue exhibited the fastest increase over time (T0 = 1.11 ± 1.86, T5 = 5.47 ± 1.70). Higher PG-SGA scores were found to be weakly explainable for aggravating fatigue (ß = 0.02 ~ 0.04). Unlike generalized additive mixed models, marginal structural models (MSM) produced larger effect values (ß = 0.12 ~ 0.21). Additionally, body composition indices showed weakly negative relationships with fatigue in MSMs one week in advance. CONCLUSIONS: The PG-SGA may be a more accurate predictor of future-week fatigue than individual body composition indicators, particularly when HADS is controlled for as a time-dependent confounder.


Assuntos
Fadiga , Neoplasias Nasofaríngeas , Estado Nutricional , Radioterapia de Intensidade Modulada , Humanos , Fadiga/etiologia , Masculino , Feminino , Neoplasias Nasofaríngeas/radioterapia , Pessoa de Meia-Idade , Estudos Longitudinais , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Adulto , Carcinoma Nasofaríngeo/radioterapia , Idoso , Composição Corporal
13.
Phytomedicine ; 121: 155080, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37757711

RESUMO

BACKGROUND: Asperosaponin VI (AVI) is a natural triterpenoid saponin isolated from Dipsacus asper Wall with documented anti-inflammatory and bone protective effects. Our previous work reported that AVI protects the liver of septic mice from acute inflammatory damage. In this paper, we further explored the protective effect and the potential mechanisms of AVI in alcoholic fatty liver disease (AFLD). METHODS: The Lieber-Decarli model was constructed to evaluate the effect of AVI on AFLD in C57BL/6 J mice. Additional in vitro work was performed to investigate HepG2 cells exposed to alcohol, then analyzed the degree of liver injury by detecting the ALT and AST levels both in the liver and serum. H&E staining and Sirius red staining were used to evaluate the histopathology variations in the liver. Further, observe lipid droplets in the cytoplasm by Oil Red O staining. We detected the expression of inflammatory cytokines with qualitative PCR; ROS, MDA, SOD, and GSH-px levels were analyzed to observe oxidative stress. Finally, exploring the activation of AMPK signaling pathway by real-time PCR and Western blotting. RESULTS: Histological examination of liver tissue combined with serum ALT and AST levels showed a significant protective effect of AVI against alcoholic liver injury in AFLD mice. Compared with the model group, AVI evidently improved antioxidant capacity, reduced inflammatory response and lipid accumulation both in vitro and in vivo. For mechanically, it was found that AVI up-regulated phosphorylation level of AMP-activated protein kinase (AMPK) and inhibited the endoplasmic reticulum stress (ER) pathway in AFLD. CONCLUSION: AVI protects mice from alcohol-induced hepatic steatosis and liver injury through activating AMPK signaling and repress ER stress, suggesting that it might be a potential therapeutic agent for AFLD.


Assuntos
Fígado Gorduroso Alcoólico , Saponinas , Camundongos , Animais , Fígado Gorduroso Alcoólico/tratamento farmacológico , Fígado Gorduroso Alcoólico/patologia , Metabolismo dos Lipídeos , Proteínas Quinases Ativadas por AMP/metabolismo , Camundongos Endogâmicos C57BL , Fígado , Saponinas/metabolismo , Estresse Oxidativo , Estresse do Retículo Endoplasmático
14.
Infect Drug Resist ; 16: 6983-6998, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37933293

RESUMO

Objective: Drug-resistant tuberculosis (DR-TB) in children seriously threatens TB control. Information on the epidemiology and characteristics of DR-TB in children in China is limited. We studied data in Shenyang Tenth People's Hospital to understand the DR-TB epidemiology in children in Shenyang. Design or Methods: We retrospectively analyzed drug resistance testing data of pediatric TB patients between 2017 and 2021, and included 2976 clinically-diagnosed pediatric TB patients. We described the epidemiology of DR-TB and analyzed the trends of DR-TB incidence. The Kappa value was calculated to assess the agreement between MGIT 960 DST and Xpert MTB/RIF for detecting rifampicin resistance. Multivariate logistic regression was used to identify the risk factors for DR-TB in pediatric patients. Results: Of the 2976 TB patients, 1076 were confirmed by MGIT 960 culture and/or Xpert MTB/RIF. Among the 806 patients identified by MGIT 960 culture, 232 cases (28.78%) were DR-TB. Resistance to the six drugs was in the following order: streptomycin (21.09%), isoniazid (9.35%), rifampin (15.01%), levofloxacin (6.20%), ethambutol (4.22%), and amikacin (3.23%). Alarmingly, 12.90% were MDR-TB (104/806), including 28 (3.47%) pre-XDR-TB. Of the 1076 pediatric TB patients, 295 (27.4%) developed DR-TB to any one drug (including 69 rifampicin-resistant cases identified by Xpert MTB/RIF only). No difference was found in the incidence of pediatric DR-TB between 2017 and 2021. Among 376 patients who were positive for both methods, using the MGIT 960 DST results as the gold standard, Xpert MTB/RIF's sensitivity for detecting rifampicin resistance was 91.38% and its specificity was 94.65%. Conclusion: Between 2017 and 2021, the DR-TB incidence in children remained unchanged in Shenyang. RR-TB, MDR-TB, and even Pre-XDR-TB require attention in children with drug-resistant TB. Xpert MTB/RIF helped to detect more rifampicin-resistant pediatric patients; thus Xpert MTB/RIF should be widely used as an important complementary tool to detect rifampicin-resistant TB in children.

15.
J Contam Hydrol ; 245: 103942, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34995934

RESUMO

Steam injection technology is commonly used to rapidly remove volatile and semi-volatile organic pollutants in aquifers, and its remediation effect is highly related to steam migration and temperature distribution. However, systematic studies on steam migration and temperature distribution across different types of aquifers are lacking. In this study, the steam migration and temperature distribution in an aquifer were investigated through a series of two-dimensional sandbox experiments with different groundwater velocities, steam injection flow rates, and stratigraphic structures. The experimental results indicated that the temperature distribution in the aquifer was related to the formation permeability and steam injection flow rate. When the hydraulic conductivity of the aquifer was lower than 10-3 cm·s-1, the heating zone in the aquifer had an H-shaped distribution, and when it was higher than 10-2 cm·s-1, the heating zone had a V-shaped distribution for a high steam injection flow rate (1 kgh-1), and an H-shaped distribution for a low injection flow rate (0.5 kgh-1). Under the same injection steam flow rate, the total area of the heating zone in the aquifers with different media was in the following order of sand particle size: coarse sand > fine sand > medium sand. Owing to the heat pipe and heat dispersion effects, the heating zone area in the fine sand aquifer was larger than that of the medium sand aquifer. Groundwater velocity did not affect the area of the heating zone. With the increase in groundwater velocity, the heating zone expanded downstream. In layered heterogeneous aquifers, the upper fine and lower coarse structures formed a steam-blocking interface, resulting in steam accumulation and temperature increase in the lower layer. These findings are significant for improving our understanding of steam migration and temperature distribution in aquifers, leading to an improved design and prediction of the steam remediation required for mitigating aquifer pollution.


Assuntos
Água Subterrânea , Vapor , Temperatura
16.
Sci Total Environ ; 828: 154422, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35276162

RESUMO

Micron zero valent iron (mZVI) was an underground remediation material, which had great application potential to replace nano zero valent iron (nZVI) from the perspective of economic and health benefits. However, mZVI was highly prone to gravitational settling, which limited its wide application for in situ remediation of contaminated groundwater. This paper was devoted to develop an efficient and economical groundwater remediation material based on mZVI, which should possess excellent stability, reactivity, and transportability. Thereby xanthan gum (XG) stabilized and Na2S2O4 sulfidated mZVI (XG-S-mZVI) was synthesized and characterized with SEM, XRD, XPS, and FTIR techniques. In terms of stability, the adsorbed XG and the dispersed XG worked together to resist the sedimentation of S-mZVI. In terms of reactivity, sulfidation enhanced the electron transfer rate and electron selectivity of XG-S-mZVI, thereby improved the reactivity of XG-S-mZVI. The hexavalent chromium (Cr(VI)) removal rate constant by XG-S-mZVI was determined to be 832.4 times than bare mZVI. In terms of transportability, the transportability of XG-S-mZVI was greatly improved (~80 cm in coarse sand and ~50 cm in medium sand). Straining was the main mechanism of XG-S-mZVI retention in porous media. XG-S-mZVI in situ reactive zone (XG-S-mZVI-IRZ) was only suitable to the media with a grain size larger than 0.25 mm. This study could provide theoretical support and guidance for the implementation of IRZ technology based on mZVI.


Assuntos
Recuperação e Remediação Ambiental , Água Subterrânea , Poluentes Químicos da Água , Cromo/análise , Ferro , Polissacarídeos Bacterianos , Areia , Poluentes Químicos da Água/análise
17.
Hortic Res ; 9: uhac137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36072832

RESUMO

The morphological diversity of leaf margin shapes is an identifying characteristic of many plant species. In our previous work, BoALG10 (α-1,2 glycosyltransferase) was predicted to be a key regulator of leaf margin shape in ornamental kale (Brassica oleracea var. acephala). An alanine and a leucine residue in the conserved domain of the smooth-margined S0835 were replaced by an aspartate and a phenylalanine, respectively, in the corresponding positions of the feathered-margined F0819. However, the expression pattern and function of this gene remain unclear. Here, we examined the expression patterns of BoALG10 using quantitative real-time PCR, and found that statistically significant differences in expression existed between F0819 and S0835 in nine developmental stages. The BoALG10 protein localized to the endoplasmic reticulum. The function of BoALG10 was then examined using complementary mutant assays. The overexpression strains phenocopied the smooth leaf margin after introduction of BoALG10 S0835 into the feathered-margined inbred line F0819. Simultaneously, irregular dissections appeared in the leaf margins of knockout mutants KO-1 and KO-2, which were generated by CRISPR/Cas9 technology from the smooth-margined inbred line S0835. Microscopic observation showed that the leaf margin cells of the smooth-margined plants S0835 and OE-3 were arranged regularly, while the cells of the feathered-margined plants F0819 and KO-1 were of inconsistent size and distributed in an irregular manner, particularly around the indentations of the leaf. This elucidation of BoALG10 function provides a novel insight into the morphological regulation of leaf margin shape.

18.
Chemosphere ; 308(Pt 2): 136229, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36041530

RESUMO

Molasses have a prominent effect on the bioremediation of Cr(VI) contaminated groundwater. However, its reaction mechanism is not detailed. In this paper, the removal of Cr(VI) with different carbon sources was compared to explore the effect and mechanism of the molasses. The addition of molasses can completely remove 25 mg/L Cr(VI), while the removal efficiency by glucose or emulsified vegetable oil was only 20%. Molasses could rapidly stimulate the reduction of Cr(VI) by indigenous microorganisms and weakened the toxicity on bacteria. The average removal rate of Cr(VI) was 0.42 mg/L·h, 10 times that of glucose system. Compared with glucose, molasses can remediate Cr(VI) at a higher concentration (50 mg/L), and the carbohydrate acted as microbial nutrients. Direct and indirect reduction acted together, the Fe(II) content in the aquifer medium increased from 1.7% to 4.7%. The addition of molasses extract into glucose system could increased the removal rate of Cr(VI) by 2-3 times, and the ions of molasses had no significant effect on the reduction. Excitation emission matrix fluorescence spectra and electrochemical analysis proved that the molasses contained humic acid-like substances, which had the ability of electron shuttle and improved the reduction rate of Cr(VI). In the process of bioreduction, the composition of molasses changed and the electron transport capacity increased from 104.2 to 446.5 µmol/(g C), but these substances could not be used as electron transport media to continuously enhance the reduction effect. This study is of great significance to fully understand the role and application of molasses.


Assuntos
Substâncias Húmicas , Melaço , Biodegradação Ambiental , Carboidratos , Carbono , Cromo/análise , Compostos Ferrosos , Glucose , Substâncias Húmicas/análise , Melaço/análise , Oxirredução , Óleos de Plantas
19.
Front Psychol ; 13: 1010033, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211893

RESUMO

Science, Technology, Engineering, and Math (STEM) education emphasizes solving problems in authentic contexts and developing 21st-century skills. It also helps to cultivate individuals possessing scientific curiosity and innovative abilities. These capacities align with China's core literacy training. Recent years have seen K-12 STEM cases flourish nationally. However, little attention has been paid to the shared characteristics of these practices, and suggestions for implementing STEM in primary and secondary schools are scarce. This paper presents commonalities in STEM practices within China from a curriculum perspective and offers recommendations for implementation based on these attributes. Specifically, this study first constructed analytical metrics via the Delphi method to assess STEM cases. Next, 51 typical STEM teaching cases in different regions of China were analyzed using these metrics. Based upon the statistical results, five characteristics of STEM cases were summarized: China's STEM education has an unbalanced geographical distribution; current practices benchmark the need for innovative talent training; most instructional content is drawn from real-world problems, but interdisciplinary integration deserves closer focus; the cases featured rich teaching activities and were conducted in a project-based learning fashion with insufficient emphasis on mathematical applications; and China seems to be holistically promoting STEM education, especially through new technologies and supplementary materials. Findings should allow instructors to better understand the intricacies of STEM implementation and to promote successful STEM cases. Recommendations are also provided to optimize the localization of STEM education in China in order to cultivate innovative and interdisciplinary talent.

20.
Chemosphere ; 296: 134015, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35182528

RESUMO

Air sparging (AS) is considered an effective remediation technology for groundwater contaminated by volatile organic compounds. However, the effects of AS remediation of heterogeneous aquifers with lenses of different permeability are still unclear, which limits the application of AS technology. In this study, the effects of different permeable lenses on nitrobenzene (NB) transport were quantitatively analysed by tracking the temporal and spatial evolutions of the NB concentration and using light transmission visualisation technology to observe airflow. Experimental results showed that the NB outside the airflow zone of the heterogeneous aquifer containing a gravel lens was rapidly removed, which is a special phenomenon. Through moisture content monitoring and colour tracer technology, the bubble-induced water circulation zone in a gravel lens was discovered during AS. At this time, the zone of influence (ZOI) included air flow zone and water circulation zone, while previous studies believed that the ZOI only contained the air flow zone. The presence of water circulation zone in the heterogeneous aquifer with a gravel lens increased the ZOI area and average contaminant removal flux by 5 and 2.3 times, respectively, compared with those in homogeneous aquifer. These findings have modified the conventional cognition about the ZOI and are conducive to an in-depth understanding of the remediation mechanisms and a better design of AS technology in heterogeneous aquifers with different permeable lenses.


Assuntos
Recuperação e Remediação Ambiental , Água Subterrânea , Poluentes Químicos da Água , Água Subterrânea/análise , Nitrobenzenos , Porosidade , Água/análise , Poluentes Químicos da Água/análise
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